Method for dettinning and producing tin compounds and other products.



PATENTED DEG.'17. 190?.

B. A. SPERRY. METHOD FORDETINNIN-G AND PRODUCING TIN COMPOUNDS AND OTHER manners. APPLIOLTIOI FILED NOV. 29, 1905.

2 SHEETS-4111131, 1.

INVENTOR Al/mw llnm lil l uuahnfin WITNESSES:

'PATENTED' DEG. 17, 1 907.

,EY.A.SPBRRY. MBTHOD'POB DBTINNING AND PRODUCING TIN COMPOUNDS AND OTHER PRODUCTS. APPLICATION FILED NOV. 29, 1905.

2 sums-sum a.

[NVENTOR WITNESSES:

UNITED STATES PATENT OFFICE;

ELMER A. SPERRY, OF NEW YORK, N. Y.

METHOD FOR DETINNING AND PRODUCING TIN COIPOUN'DS AND OTHER PRODUCTS.

Patented Dec. 17, 1907.

Application filed November 29. 1905. Serial No. 289.581.

To all whom it may concern:

Be it known that I, ELMER A. SPERRY, a citizen" of the United States, residing at Brooklyn, New York, in the county of Kings and State of New York, have invented new and useful Improvements in Methods for Detinning and Producing Tin Com ounds and other Products, of which the fo lowing is a of its reacting forms, including anhydrousthis material whereby the various comnier.

specification.

This invention is based on the chemical reaction between chlorin and metallic tin which produces stannic chlorid. Tin or any tin bearing material, such for instance as tin Ag attacked or oxidized; as little as possible.

plate scrap ma be considered as suitable for the supply of t e metal.

The invention consists in i a process or method of operation whereby chlorin in any chlorin, gaseous chlorin, pure or diluted with moisture or, other gases or va 01's, or chlorin compounds maybe success y employed in carrying out the process economically, continuously and on a commercial basis. The stannic chlorid immediate] minal product, but the invention extends to steps for the treatment and purification of cial forms of the chlorid as well as other products, including metallic tin, are produced.

A further object of the invention is to preserve any inert bodies or residues associated with the tin from attack by the reagent employed. s

It also consists in the preliminary treatment of the scrap and in various steps of treatment of both scrap and product through- 1 out the operation of the process, all of whlch are peculiar to m process, being described in full detail herein, and pointed out in the claims attached hereto and forming a part hereof.

The accompanying drawings serve the pur ose of illustrating one form of apparatus wit .which the process-may be carried into effect. 1"

In these drawingsFigure 1-illustrates a half of a basket Figs. 4 and 5are, details illustrating parts of the apresultin from, the reaction may be consi ered as t e ters Fig. 2 is two half baskets,- assembledj'intofa spherical package adapted tocontain tightly compacted tin scrap. Fig. 3 represents a'diagrammatic view of suitab e "means for carrying out the process; this fig ure is continued on the second sheet.

paratus by means of which the processis carried forward.

Before going into a detailed description of,

all ot er foreign metals, inasmuc as scrapcontaining more than .04 per cent of foreign metals is unfit for purposes of making steel,

and therefore of very little value as there is practically no market for impure scra ain the surface of the scrap should 0 Again; the process should be as continuous as practicable, in this manner avoiding unnecessary expense for labor. In attaining these objects I avail myself, amongother things, of a discove which I have made that hydrated stanmc chlorid and -stannic chlorin solutions, es ecially when containing chlorin are extreme y active in dissolving or separating tin from other metals or frm tin bearing materials, such as tin plate, but the solutions of stannic chlorid are extremely corrosive and do not suspend their action when the tin has disa peared from the iron or steel plate but go arthcr and attack the plate itself. I have discovered, however, that this is not true to any ap reciable-extent when the attack is made hydrated stannic chloridf under seal of ,anh drous stannic chlorid or in the presence of t e latter, though not necessarily at all times under seal thereof; this contemplates the admission of water less than that required to make solution.

So far as I have been able to ascertain the increase in the activity of both the hydrate and the solutions of stannic chlorid is as follows: Beginning with'the hydrate contain ing three waters 0i crystallization as increasing amounts of water are added until a point at about fifty to forty degrees on the Baum scale (for llquids heavien than water) is reached when the activit gradually falls away more and more as ad ition'al quantities of water are added to the solution; the activity of the hydrate is -also found to increase with the increase of temperature, to rise very rapidly to sixty-five (65) degrees centigrade or thereabouts and after that more graduall until a point of about ninety degrees is reached'where it seems to be somewhat more activethan at sixty-five (65) degrees. The

suitablein points of electric conductivity and i activity for use as such, and I find that by so utilizing this function of the hydrate I am 1 enabled to more completely strip the scrap and free it from foreign metal content than b simple chlorination. The electrolyzation a so tends to correct any tendency of the liquids to pass from the stannic to the stannous state. The recovery of tin is also greatly facilitated by utilizing the hydrate as an electrolyte. I thus render a material or combination of materials in liquid state more active than anhydrous stannic chlorid doubly active by use of the electric current, a thing impossible with the anhydrous inasmuch as it is a non-conductor of electricity. I thus develop conditions which are extremely fa vorable to the complete removal of all foreign material, inasmuc as making the scrap the anode in such a bath helps to remove the last traces of tin, together with some other metals, such for instance, as lead and antimony. The presence of the hydrate again is found extremely advantageous in the practical operation of the process as it avoids the necessity of drying the chlorin,' as complete drying is necessary when the anhydrous chlorid is exclusively em loyed.

In the present process jam enabled to use ordinary wet chlorin even when associated with air or other gases which themselves may bring water into the system, and instead of drying, which is most diflicult and expensive 'with chlorin gas I may under some circumstances inject extra water; and moreover the rocess goes forward completely under 0011(itlOI1S as stated .vhere air or gases are entrained witht-he chlorin, as provision is made for recovering all values which are taken from the system either as gases or va- I pors and which may be either entrained, dissolved or taken up by such air or gases; this step in the process forms an essential part thereof. y

In the preliminary preparation of the scrap, it may be divided into two classes; cuttings, which is usually from new tin plate, and manufactured scrap, which is for the most part old scrap, such as cans. etc; in some instances no classification is made. The scrap may be put through he process in any form thought desirable. in mass or rammed tightly into retainers. as illustrated herein. The class is put into the retainers or baskets direct. The second class may have previous treatment before being placed into these baskets. This treatment it used consists first in a rough mechanical classification: then heating for melting llder and \Yt akening joints. Third, while hot. dismembering and opening all joints. The last process being preferably done with such violent-e as to throw off all solder possible, which is recovered. This scrap may then be placed in half .baskets indicated by A and A,

which are'then brought together in the form t of a sphere as indicated by A, and may be rammed into molds before basketing. The

baskets are practically made. of steel net or wires meridionally disposed and secured to a circular ring at the joint. The rings are detachably secured to each other. The tin scra or cuttings are now preferably washed in a ath of caustic alkali in tank B, drained in tank C, and dried in oven D at an elevated temperature, whereupon they are in'readimess to join the other baskets A, in the farther steps of the operation and preferably while still heated from the drying process.

In nearly all the steps it is designed to han-v dle these spherical containers filled with scrap devices may be employed for rolling or otherwise causing motion to be imparted to these spheres in their transit through the various stages of process. One mans that may be employed is a device similar to a hollow revolving screen which is slightly inclined from end to end, upon the revolving of which the spheres introduced at one end gradually work their way to the other, after having rotated in' practically every plane possible through the double motion thus imparted to the spheres. The rotation is valuable from the fact that especially in some of the steps of the process, such for instance, as drying and evaporating, the universal motion imparted serves to dump and eject any material which would otherwise be trapped and retained in an angle or corner of the compacted scrap as packed and retained in this state as by the containers A. In this state the agitation or motion is also effective in eliminating any ai. that may be entrapped or entrained as the hot masses. much hotter in fact than the reaction chamber itself. are introduced i therein under-seal; the agitation is also very advantageous in aiding the distribution and absorption of the chlorin throughout the anhydrous liquid or liquids present, thus, not

5 only preventing impoverishment, but aiding in maintaining the fullest possible degree of chlorinization of the liquids; the chlorin being present in excess is thus held in suspension and is entrained as well as dissolved. It is only in this state, viz: the state which f we may denominate as supersaturation, that automatically, and to this end a number of preferably while yet hot, they are introduced mi/nates below the surface of liquid '0, which is of some height, for the purpose of preve'nting the egress of fumes contained in the vesse E, in which is a revolving screen a, handling the spheres A, A, A, etc. for the most part below the surface of the chlorid. The

i'evolving of thisscreen, or parta, also serves I to agitate the chlorid, which thus greatly aids in distribution of the chlorin throughout thennass and also in presenting freshly Q chloriflated liquid to the tinned surfaces.

- The rotation may be effected through a .wheel E, the shaft comingout through a stufling box b, The whole is inclosed within '25 a steam or other jacket F, by means of which the temperature of the chlorid c is governed.

- This jacket may be either'heat absorbing as when containing water or heatemitting as whenv containing steam according to the necessities of the case. vBy their aid-the contents may be held at any temperature required, preferably above the *congealing' point of the stannic hydrate with 3 or 5 wa- 'ters' of hydration, including considerations 3,5, such as, primarily, the or of the reaction, also size of apparatus, ra 'ati surface, etc. The chlprin or gases containing chlorin which may or may not be commingled with water or Water a to tank E, throu h pipe G and the surplus liq- 'uids drawn 0% through ipes H or H; the

a former being at the over fl dw level of the tank The surplus gases are suitably drawn off as by jacketed pipe E? leading to comp'artment' I.

' The revolvi screen is insulated at its points, a and a and stufling box b,so that as the spheres are revolvin in the screen a, an electric current is passed into the screen inhe eluding ,the spheres, which thus become anodic, by virtue of the hydrated stannic chlorid present which acts in the capacity of an electrolyte, as described and out on the walls of the tank E, which thus become the cathodeQ The lead that becomes electrically separated from the scrap falls to the bottom of the tank E, while the tin which tends to attach itself to the cathode or plate thereon is immediatelv seizedupon by the excess chlorin dissolved or otherwise held in the bath and converted together with any stannous chlorid into stannic chlorid.

The farther steps of the rocess are very simpleand consist of suita ly ejectingthe spheres from the revolving screen a, and

cm the drier D into the tube E, which terrs are introduced into through an opening E" leading to the washing compartment I, which is shown as being furnished with another revolving screen a where the spheres are washed in an anhydrous liquid preferably anhydrous stannic chlorid and at a temperature which may be somewhat higher than that maintained in the treating bath. This temperature should be above the congealing point of the hydrate and below the boiling point ofthe stannic chlorid or. other washing medium.

From the washing tank I, the spheres A are passed to the chamber J, which is maintained preferably at a temperature of 116 degrees or above, where the scrap is drained, evaporated and dried, and thus freed from the washing liquor together with any stannic chlorid which may still cling to them. It is here where the revolution and universal motion referred to above, through all'planes is-also advantageous as any pocketed chlorid may escape and be drawn or driven off during this process of evaporation. If any hydrate remains from the washing in anhydrous liquids, it is found to evaporate very rapidly at a suitable temperature. The vapors and gases passing from this chamber especially with the vaporizing anhydrous chlorid present, also the vapors from the washing liquid, are led in jacketed pipes as pipe 'K, held at a temperature pre erably eighty (80) degrees or more, to a condenser or condensers L, where the gases are suddenly cooled and where both the anhydrous liquid or liquids from tank E, I or J together with any hydratedstannic chlorid is recovered in whole or part; the former being led oil' by pipe X; the latter being caught in receptacle M. These condensers serve all the tanks, E, I and J, which are connected by the jacketed passages as shown. Any residual gases passmg from any of these tanks and through the condensers L, are led in the jacketed pipe X to the tower T, and there treatedwith asuitable solvent for the vaporsor gases passing, as, for instance, when anhydrous chlorid" is present water may be em loyed, infa suitable manner for production 0 .solutions of stannic chlorid.

A plurality of condensers is employed and valyes Z and Z, provided so that one may be shut off and freed of any solids such as crystals and hydrate, while the other is condensing. It will be seen that the function of condenser L is twofold, as previously stated by me in another branch of-this art in connection with the production of anhydrous stannicchlorid, namely, that of both coinlensing and separating hydrated and anhdyrous stannic chlorid one from the other, the crystals remaining upon the walls of the condenser, while the'anhydrous trickles down g and is remo vcd through pipe M, the hydrate being removed, either'meohanically or by heating above its melting pointwhereupon it runs out and is caught in receptacle M. Itavill thus be seen that the products are first heated to insure li uefaction of the hydrate, which otherwise is found to deposit-and plug the pipes solidly, afterward they are cooled to condense the vapors and also to solidify and thus separate the hydrated from the anhydrous stannic chlorid, as hereinbefore stated.

A suction fan or blower O is shownconnected' with the tower, which produces the necessary movement'of the gases throughout the system, and is practically so adjusted as by using the valve 0, that the pressure is almost at equilibrium; with the surrounding atmosphere throughout the system, same being preferably somewhat inhalent or negative to avoid emission of the noisome gases and vapors.

It now remains to explain the treatment of the products, which are hydrated and anhydrous stannic chlorid and solutions thereof. These were associated, as from tank E, are first strained or filtered hot to free them from foreign materials, then allowed to cool .and again strained, whereupon the hydrate so distilled a still P may be used, from which the vapors may be condensed in an apparatus similar to condenser L. The product oflthis distillation is then ready for market.

The foregoing heavy chlorids together with the solution of stannic chlorid, coming from the tower, constitute an example of the tin compounds which result from the processes described. It now remains to describe the step by which metallic tin is recovered from the chlorid of tin. By referring to Fig. 5, it will be seen that a vat Q, is illustrated as containing certain anodes, e, e, e, etc., which are of the class known as insoluble anodes which are coupled to a common electrical conductor 9. The vat Q together with the connected sheets h, h, k, may constitute the cathode and are provided with electrical connections. The vat Q is surrounded by a jacket F or other suitable means whereby its temperature maybe controlled or maintained at a suitable point. the chlorid resulting from the previous steps of the process or such portion thereof as is to be treated for tin in the metallic state or other products. In this portion of the plant the chlorid and preferably the hydrated stannic or stannous chlorid is elrctrolyzed,

Into this vat is placed under such conditions that tin is thrown out or deposited uponthe cathodes, 72, 72, I1, etc. The deposit thus secured from the cathodes may be stripped from the surfaces thereof or the cathodes themselves may consist of pure metal-as in the case of copper refining, in which case the base plate as well as the deposited metal may be melted together and cast into ingots for the market. The chlorin coming off the anode compartment is collected and returned to the system through pipe R. The supply of chlorid may be introduced through pipe S.

It will be noticed that the process described ierein is essentially a continuous one.

I do not wish to be limited by the foregoin method of recovery of tin from the chlorids, or other compounds of tin derived from the chlorid. Other methods exist which are purely chemical and may be employed in lieu of the electrical method described, and the invention extends to any method by means of which the tin may be thrown out from the compounds of, tin obtained either primarily or as a secondary product from the treatment described and claimed herein.

In the foregoing description of my invention I have set forth the method of operation, together'with its various steps. It should be understood that while the steps are described in the order in which they are employed herein to illustrate one system of procedure, yet some may be used without the others, and the steps may be varied as to detail, as circumstances demand, and the invention extends to such use.

I claim: 7

1. The process of detinning which consists in reacting on the masses to be detinned with chlorin in the presence of stannic chlorid hydrate.

2. The process of detinning which consists in reacting on the masses to be detinned with chlorin dissolved in or carried by stannic chlorid hydrate.

'3. The process of detinning which consists in reacting on the mass to be detinned with chlorin in the presence of stannic chlorid hydrate and controlling the temperature.

4. The continuous process of detinning which consists in drying the tin scrap, reacting' on same with chlorin in the presence of anhydrous stannic chlorid, continuously supplying the scrap and the chlorin and controlling the temperature of the reaction.

5. The process of detinning which consists in reacting on the masses to be detinned with chlorin and water vapor in the presence of an anhydrous liquid.

6. The process of detinning and producing stannic chlorid which consists in reacting on the masses to be detinned with chlorin in the presence of moisture and controlling the temperature of the reaction.

7. The process of detinning and-producing 8. The'process of detinning which consists in reacting on the masses to be detinned with chlorin and moisture in the presence of an anhydrous liquid in which the chlorin is dis-v solved in whole or part.

9. The process of detinning which consists in reacting onthe masses to be detinned with chlorin and water vapor in the presence of a suitable anhydroiis liquid producing thereby stannic chlorid and stannicchlorid hydrateand maintaining the temperature at or above the congealing point of the hydrate.

10. The process of recovering tin from tin scrap which consists in reacting upon the mass to be detinned'with chlorin in the presence of stannic chlorid, stannic chlorid hydrate and electro-depositing tin from the chlorid.

11. The process of recovering tin from tin scrap which consists in reacting upon the mass to be detinned with chlorin in the presence of stannic chlorid hydrate, adding water and then throwing out tin from the chlorid.

12. The process of det which consists in treating the mass to be etinned with a suitable anhydrous liquid into which is fed chlorin and moisture.

13. The method of making stannic chlorid from tin plate scrap,.-'tin, or other tin'bearing material which consists in reacting on such material with chlorin in the presence of anhydrous stannic chlorid at a temperature below the boiling point of anhydrous stannic chlorid, and maintaining the reaction by supplying gaseous chlorin to the reacting mass.

14C. The process of detinning which con sists in reacting upon the mass to be detinned with chlorin in the presence of stannic chlorid,

driving off the adhering chlorid by distilla tion and recovering such chlorid."

I 15. The process of detinn'ing which consists in reacting upon the mass to be detinned with chlorin in the presence of stannic chlorid, washing the detinned mass in a suitable anhydrous liquid and distilling off the liquid from such mass.

- 16; The process of detinning which conslsts m reacting upon the mass to be detinned with chlorin in the presence of stannic chlorid,

agitating the detinned mass while separating the chlorids therefrom.

17. The process of detinning which consists in reacting upon the mass to be detinned with chlorin in the presence of anhydrous stannic chlorid, an electrolyte and an electric current.

18, The process of detinning which con sists in reacting upon the mass to be detinned chlorin in the presence of stannic chlorid hydrate.

21. The process of detinningwhich con sists in reacting onthe masses to he detinned with chlorin in the resenc of stannic chlorid and moisture, to ucing stannic chlorids, re-

moving the c orids at an elevated temperature, and separating the anhydrous from the hydrated ch orid.

22. The process of detinning which consists in reacting on the massesto be detinned I with chlorin in the presence of stannic chlorid, producing stannic chlorids, separating the anhydrous from the hydrated chloride, and separatingchlorin from the anhydrous product.

' 23. The process of detinning' which con- .sists in reacting withchlorin uponthe masses to be detinned in a chamber, heating the products of such reaction as they are re moved from the chamber.

24.- The process of detinning which consists in reactingwith chlorin upon the masses to be detinned in a chamber, controlling'the temperature of such chamber, and heating the products of such reaction as they are-removed from the chamber.

25. The process of detinning which consists in reacting with chlorin and moisture u on the masses tobe detinned, controlling t e temperature of such reaction and drawing off the tin bearing products through heatecl'discharge devices. 1

26. The continuous process of detinning which consists in reactin with chlorin upon moving masses to bedetmned in a plum ity of chambers under conditions of temperature thus produced for the purposes specified.

27. The process of detinning which consists in reactingon the mass to be'det'innerl control of such chambers, and first heating and then cooling the tin-bearing products constituting an electrode in an electric air cuit with moist chlorin in the presence of an hydrous stannic chlorid.

28. The process of detinning which consists in compacting the scrap, heating same, reacting upon the heated mass with chlorin and controlling the temperature of the was tion.

29. The process of detinning which consists in reacting on the masses to be detinned constituting an electrode iii an electric circuit with moist chlorin in presence of anhy- 'zlrous and hydrated stannic chlorid.

30. Theprocess of detinning which consists in compacting the scrap, heating same, reactingupon the heated mass with chlorin and controlling the temperature of the reace tion the temperature of the scrap being .higher before being introduced than that of the reaction vessel.

31. The process of detinning which con sists in reacting upon the masses to be detinnedtvrth chlorin 1n the presence of stannic chlorid, driving oil the adhering; chlorid by distillation in a current of gas and recovering the -chlorid. I

. 32'. Theprocess of detinning which consists in reacting upon the masses to be detinned with chlorin in the presence of stannic chlorid, driving oil the adhering; chlorid by heat and recovering anhydrous and hydrated tin chlorid.

.33. The process of detinning which cons sts 1n compacting the sore reacting upon the compacted mass with c or n under conditions of mechanical motion or agitation of such mass and controlling the'temperatureof such reaction,

1 34. The process of detinni'ng which con sists in reacting upon the masses to be detinned With chlorin diluted .With air in the presence of stannic chlorid, driving off the adhering chlorid from the mass. by heat in the presence of a moving gaseous body consisting of the air entrained with the chlorin and recovering the chlorid therefrom.

35;. The process of detinning which consists in reacting upon the mass to be detinned With chlorin and agitating the detinned mass While separating the chlorid therefrom by heat.

36. The process of detinning which consists 111 reacting on the masses to be detinned with chlorin in the presence of stannic chlorid producing stannic chlorid therefrom with excess of chlorin and removing chlorin from the product.

37. The process of detinning which consists in compacting the scrap; reacting upon the compacted mass with cv lorin dissolved and carried by a suitable liquid under conditions of mechanical motion or agitation of such mass together with the liquid and controlling temperature of the reaction.

The'process of detinning which consists in reacting on the mass to he detinned with chlorin in the presence of stannic chlorid hydrate and a body of anhydrous liquid and controlling the temperature ofthe reac- 0 tion.

39. The process of detinning which consists'in compacting the scrap, reacting upon "with chlorin in the presence of stannic chlorid hydrate, washing the detinned inass'in a suitable anhydrous liquid and distilling oil the liquid from such mass.

42. The process of detinning which consists in reacting upon the mass to he detinned with chlorin, ashing the detinned mass in a suitable anhydrous liquid, and distilling oii' the liquid from such mass and re-claiming the liquid.

43. The process of detmnmg which consists 1n reacting with dlssolved gaseous chlorin upon the'masses to be detinned in a chamber controlling the temperature of such chamber'and heating the products of such reaction as they are removed fromthe chamber, and then cooling same to condense the vapor.

4a. The process of sists in reacting sith gaseous chlorin upon the masses to be detinncd in presence of moisture, controlling the temperature of such reaction and dram ing oil the tin bearing products through heated discharge devices.

45. The continuous process oi detinning ahich consists in reacting with gaseous chlorin dissolved in w hole or part in a suitable liquid upon moving masses to be detinncd in a plurality of chambers under conditions of temperature control of such cl'lamher.

46. The method of making stannic chlorid from tin plate scrap or tin nearing material which consists in reacting on such material with chlorin in the presence of anhydrous stannic chlorid at a temperature below the vaporizing point of stannic chlorid, maintaining the reaction by supplying gaseous chlorin to the reacting mass, and separating the stannic chlorid from the undissolvcd material or residue.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ELMER A. SPERRY. lVitnesses 1 CHAS. J. Fn'r'rnnnu, EUGENE T. BURoEssER.

detinning which con- 

